Method of corrugating sheet material



May 19, 1936. B. FRANGHIA METHOD OF CORRUGATING SHEET MATERIAL Filed May 6, 1955 mm Km a Mn N. N n

ww Wm k a Patented May 19, 1936 MATE Byron Franghia, Paris, France J v Application May 6, 1935, Serial N0. 20,04?

; In Luxembourg May 7, 1934 4 Claims.

This invention relates in general to the working of thin sheet material and more particularly to a device for the formation of symmetric corrugations in such material.

In the shaping of objects of very thin sheet material, such as metal, paper, cardboard and the like, it has been found advantageous to use a circular cut-out blank and transform it into a cylindrical or frusto conical shape by means of a stamping punch. Such a transformation, however, requires, if there is no rolling or stretching of the material, a corrugation of the sheet or blank since the surface obtained is not developable.

It is therefore an object of the invention to provide a simple and efficient apparatus for producing symmetric corrugations in such thin sheet material.

With the foregoing and other objects in view, the invention resides in the combination of parts and in the details of construction hereinafter set forth in the following specification and appended claims, certain embodiments thereof being illustrated in the accompanying drawing, in which:

Figure 12' is a view in vertical section through a portion of the apparatus.

Figure 2 is a similar view of a modification thereof.

Figure 3 is a diagrammatical showing of the opposed staggered corrugating pawls engaging the sheet material prior to the corrugation thereof.

Figure 4 is a similar showing of the pawls in a midway position in their movement to produce the corrugations in the sheet material.

Figure 5 is a similar showing of the pawls fully moved to form the corrugations.

Figure 1 shows a form of my invention wherein two series of opposed staggered pawls may be employed for producing the corrugations. Here the stationary upper frame is shown at 9 in which the stamping punch 6 is reciprocated by suitable means also into the lower frame ID. The blank of sheet material II is shown clamped between a series of upper pawls I2 and lower pawls I3. Each pawl I2 is pivotally mounted on a wire I4 carried by the upper frame 9. Movable on the upper frame 9 is a ring I5 to which is pivotally connected at I6 2. link II, which latter is pivotally connected at I 8 to the pawl I2. Each lower pawl I3 is similarly pivoted about a wire I9 fitted in the lower frame I0. Each pawl I3 is also connected at 20 to a link 2|, which in turn is pivotally connected at 22 to a ring 23 on the frame I 0. These two series of pawls are both arranged radially at intervals about the opening in the frame through which the punch reciprocates. The pawls I2 of one series are also arranged in staggered relation to the pawls I3 of the other series, there being sufficient clearance to allow the pawls I2 ofv one series to pass between the pawls I3 of the other series. In doing so they move from their respective positions shown in Figure 3 into those shown in Figure 4. In doing so the sheet material held therebetween is corrugated in the manner shown in Figure 4.

The punch in Figure 1 is shown at the beginning of the operation in contact with the blank I I. As soon as the punch causes the blank to descend, the pawls I3 of the lower series are rotated inwardly, drawing or forcing those of the upper series inwardly about their pivots to bring about the symmetric corrugation as shown in Figure 4. An upward movement of the punch returns the device in readiness for another operation on another blank.

As a means of simplification, springs instead of toggle joints may be used, as shown in Figure 2. Here the toggle joints of Figure 1 are replaced by tension springs 25 connected at 26 to the lower frame I 0 and to lugs 24 which are outwardly disposed with respect to the axis I9 of rotation of the pawls I 3 so as to urge these pawls I3 inwardly about their pivots. The frame 9 is provided with a flange 9 to which is secured a compression coil spring 28. This spring 28 is also secured to a collar 21 loosely carried by the frame 9. The downward pressure of the punch against the blank and the supporting pawls I3 is thus resisted by the return springs 25. Likewise the downward pressure of the collar 21 on the upper pawls I2 is resiliently partially absorbed by the spring 28. The resulting action of the pawls brings about the symmetric corrugation shown in Figure 4 in a like manner to that described in connection with Figure 1.

I claim:

1. In a device for corrugating blanks of thin sheet material, a series of radially disposed pivoted pawls for supporting said material, a reciprocatory member for forcing said material and said pawls downwardly about the pivots of the latter, means arranged in spaced staggered relation with respect to said supporting pawls whereby the relative movement of the latter causes the sheet material clamped therebetween to be corrugated, said means comprising rigid members carried by said reciprocatory member.

2. In a device for corrugating blanks of thin sheet material, a series of radially disposed pivoted pawls for supporting said material, a recip- UNITED STATES PATENT Q m -fif? 'rocatory member for forcing said material and said pawls downwardly about the pivots of the latter, means arranged in spaced staggered relation with respect to said supporting pawls whereby the relative movementof the latter causes the'sheet material clamped therebetween to be by the relative movement of thelattercauses-the sheet material clamped therebetween to becorrugated, said means comprising a series of 0p- 20 posed staggered pawls for clamping said material therebetween, said both series of pawls being provided with toggle j oints for regulating the relative 'movement between the two series of V pawls.

4. Ida device for corrugating blanks of thin sheet material, a series of radially disposed pivoted pawls for supporting said material, a reciprocatory member for forcingisaid material and said Vpawls :downwardly about the pivots of the latter, meansarranged in spaced staggered relation with respect tosaid supporting pawls where- 'by the relative movement of the latter causes the sheet material clamped therebetween to be corrugated, said means comprising a series of opposed staggered pawls for clamping said material therebetween, said last named'pawls being spring actuated to yieldingly resist the downward movement of said reciprocatory member instigating the corrugating operation. l

BYRON FRANGHIA. 

